1. Field of the Invention
The present invention relates to a digital data recording technology, in particular to a recording/reproducing technology for recording digital data on rewritable optical disks.
2. Description of the Related Art
An operation called “certification” has so far been implemented to improve the reliability of recording information on rewritable optical disks such as DVD-RAM and the like. This operation is carried out in order to improve the reliability of recording information by managing the scratches, stains, dusts, finger prints and the like on the recording surface of optical disks as described in the Japanese Patent Laid Open Publication 2001-6172 as follows: “In this ‘certify’ mode, defects on an optical disk are certified. In this mode, the data on the optical disk are actually read out from the inner circle to the outer perimeter of the optical disk to detect the defects that have developed on the optical disk. And upon discovery of a defect, a replacement sector in the place of this defect is allocated to a spare area set in advance on the optical disk. This replacement sector is allocated differently depending on the specification of each optical disk. However, the information is written as a defect list at the end of the lead-in area located on the inner circumference side of the optical disk or at the top of the lead-out area on the outer circumference side. At the same time, the defect list is registered in a memory located in the recording apparatus.” Incidentally, in a certification operation it is necessary that, after data are recorded on the optical disk, dummy data and the like different from the user data be recorded once on the optical disk by reproducing the data of the optical disk. Here, much time is necessary to record dummy data on the whole optical disk. Accordingly, it is proposed that certification and user data be recorded at the same time as described in the Japanese Patent Application Laid Open Hei 11-242565 as follows: “Therefore, the object of the present invention is to provide an initializing method of rewritable recording mediums and an initializing apparatus suitable for recording mediums of a large capacity. Another object of the present invention is to provide an initializing method of rewritable recording media that can be initialized while data are recorded without devoting any special time for the initialization of the whole recording medium and wherein the reliability of the recorded data can be secured and an initializing apparatus capable of performing the processing. Another object of the present invention is to provide an initializing method and an initializing apparatus for initializing rewritable recording mediums on which data can be recorded even if the whole area of the same is not initialized.”